the gravity of a sin depends on the species rather than on a circumstance of that sin. Accordingly we must assert that, if we consider the condition attaching to these persons, the man's sin is the more grievous, because he was more perfect than the woman.*

*viz., Adam should have known better and corrected Eve.

As regards the genus itself of the sin, the sin of each is considered to be equal, for each sinned by pride. Hence Augustine says (Gen. ad lit. xi, 35): "Eve in excusing herself betrays disparity of sex, though parity of pride."

But as regards the species of pride, the woman sinned more grievously, for three reasons:

Because she was more puffed up than the man. For the woman believed in the serpent's persuasive words, namely that God had forbidden them to eat of the tree, lest they should become like to Him; so that in wishing to attain to God's likeness by eating of the forbidden fruit, her pride rose to the height of desiring to obtain something against God's will. On the other hand, the man did not believe this to be true; wherefore he did not wish to attain to God's likeness against God's will: but his pride consisted in wishing to attain thereto by his own power.

The woman not only herself sinned, but suggested sin to the man; wherefore she sinned against both God and her neighbor.

The man's sin was diminished by the fact that, as Augustine says (Gen. ad lit. xi, 42), "he consented to the sin out of a certain friendly good-will, on account of which a man sometimes will offend God rather than make an enemy of his friend. That he ought not to have done so is shown by the just issue of the Divine sentence."

It is therefore evident that the woman's sin was more grievous than the man's.

Perhaps I'm confused, your first statement says Adam and Eve are Both responsible, and Your last, Only Adam is responsible. Understanding that both did sin, isn't it the Churchs teaching that Adam was Responsible to Gaurd and Keep the Garden?
– MarcNov 1 '18 at 11:56

@Marc Adam and Eve are Both responsible for their own personal sin, but only Adam is responsible for transmitting Original Sin to his descendants.
– GeremiaNov 1 '18 at 18:31

1

I hear you, and understand your point. I’m guessing that I’m not making myself clear. As the person given the command to Gaurd and keep, Eve was not responsible because Adam should have prevented the disobedience. When Eve bit the apple, she was tricked, and Adam did not perform his ministerial duties, even blamed Eve who did not have the responsibility. I understand that sin was passed through Adam, but I’m not sure Eve was guilty of the sin. I’ll look more into it.
– MarcNov 1 '18 at 18:43

Let us take into consideration the following passages taken from
Scripture or the Catechism:

1.Like Adam, they [Israel] have broken the covenant— they were unfaithful to me there. (Hosea 6:7)

2.Therefore, just as sin entered the world through one man….death reigned from the time of Adam to the time of Moses, even over those who did not sin by breaking a command, as did Adam…. (Rom 5:12, 14)

3.For as in Adam all die, so in Christ all will be made alive. (1 Cor 15:22)

4.All men are implicated in Adam’s sin, as St. Paul affirms: “By one man’s disobedience many (that is, all men) were made sinners”: “sin came into the world through one man…. (CCC # 402)

5.Following St. Paul, the Church has always taught that the overwhelming misery which oppresses men and their inclination towards evil and death cannot be understood apart from their connection with Adam’s sin….(CCC # 403)

6.How did the sin of Adam become the sin of all his descendants? The whole human race is in Adam “as one body of one man”.293 By this “unity of the human race” all men are implicated in Adam’s sin, as all are implicated in Christ’s justice. (CCC # 404)

In Genesis, God specifically told Adam (not Eve) that the entire earth was cursed because Adam had allowed Eve to persuade him to eat of the fruit, and also that he would die (Genesis 3:17-19).

Even St. Thomas Aquinas states in his Summa that Adam was responsible for transmitting Original sin to the entire human race and not Eve:

The solution of this question is made clear by what has been said. For it has been stated that original sin is transmitted by the first parent in so far as he is the mover in the begetting of his children: wherefore it has been said that if anyone were begotten materially only, of human flesh, they would not contract original sin. Now it is evident that in the opinion of philosophers, the active principle of generation is from the father, while the mother provides the matter. Therefore original sin, is contracted, not from the mother, but from the father: so that, accordingly, if Eve, and not Adam, had sinned, their children would not contract original sin: whereas, if Adam, and not Eve, had sinned, they would contract it. - Whether if Eve, and not Adam, had sinned, their children would have contracted original sin?